DESCRIPTION: Dr. Richard Dutton and co-organizers will host a small meeting of scientists who have made important contributions to the study of immunological memory, immunity to infectious disease, and lymphocyte homeostasis in September, 1998 at the Trudeau Institute, Saranac Lake, New York. The goal is to review the most important unanswered questions in a field that is vital to the development of effective vaccines. The organizers have chosen a discussion format, without formal presentations. They will disseminate the information gleaned from the meeting and rapidly publish it as a commentary on progress in this field.